This proposal seeks two-year funding for the analysis of data collected by the "Boston Demonstration of Outreach for AIDS Prevention" (Project Outreach). The Boston study is part of the National AIDS Demonstration Research (NADR) project investigating the role of outreach in preventing the spread of AIDS among IVDUs. In addition to participating in the national evaluation, Project Outreach is carrying out its own local evaluation which compares a high-intensity outreach program with a standard program. The study employs a quasi-experimental design involving three Massachusetts communities, one of which (Cambridge) receives the enhanced outreach program while two others (Lynn and Brockton) receive the standard program. The support requested will be used to analyze process and outcome data from this local evaluation. Since its inception on March 1, 1988, Project Outreach has collected baseline interview data on risk factors for over 1000 IVDUS. Over 99% have given blood for an HIV test. Interviewers have been successful in collecting six month follow-up data on over 70% of the sample. The enhanced intervention has been fully implemented in Cambridge. To monitor other AIDS prevention efforts in the three research sites, the staff is conducting an on-going survey. Early analyses support the hypothesis that HIV sero-conversion rates are lower in the enhanced site than in either of the two control sites. Cambridge has a 1.9% six month conversion rate; Lynn and Brockton have rates of 5.6% and 12.1% respectively. These are the first control-group results to be reported on the efficacy of outreach in preventing the spread of HIV. The two years requested are necessary for analyzing both six and 12 month outcome data and for integrating local data with data from other projects in the NADR program.